I would highly recommend Tiki ( http://tiki.org/ ) as an option as it will probably have every feature you need ready to go. Wiki for main content, forums, article publishing, blogs, forums, chat, calender, data trackers, tons of starter themes, video conferencing, file/image galleries.. the works. The v10 beta is very stable and although it is a bit of a pain to configure initially since the number of options are overwhelming, once it is set up it really rocks. Getting good performance can be a bit tricky, however if you set up the APC module, enable the minify js/css features, and get gzip and proper caching set up on the web server it can be very very fast even on a budget VPS.

JavaFX, a technology by sun which will let developers write "rich internet applications" using a Java-esq language which has been in development for quite some time now has finally been released, joining rather late to the game. Also it requires it's own plugin which will be a hefty barrier to entry.

So, it will include Audio/Video support, and it is using codecs from On2. I don't think that this means the codecs are free in any sense of the term, just that Sun is paying the cost of licensing these codecs for the developers using JavaFX. Nevertheless, good codec support is always a good thing.

Kind of deflates the "standardized, cross-platform" claim...

So, the download they offer you includes the software to run the software you write, a plugin for eclipse and netbeans which are the two leading Java development environments, and some plugins for a few Adobe products to move stuff from them into the JavaFX world.